1-cyanobicyclo(1.1.0)butanes



United States Patent m 3,530,163 l-CYANOBICYCLOH.1.0]BUTANES Henry K. Hall, In, Wilmington, Del., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware No Drawing. Continuation-impart of application Ser. No. 534,673, Mar. 16, 1966. This application Nov. 26, 1968, Ser. No. 783,453

Int. Cl. C07c 121/46 US. Cl. 260464 3 Claims ABSTRACT OF THE DISCLOSURE (1) Monomers of the formula wherein R R R and R which may be alike or different, are hydrogen or hydrocarbyl of 1 through 18 carbon atoms free of aliphatic carbon-to-carbon unsaturation; and

(2) A process for preparing the foregoing monomers, which are useful in the preparation of polymers which in turn find a variety of applications as tough, non-brittle, self-supporting films or fibers.

CROSS-REFERENCE T 0 RELATED APPLICATION This application is a continuation-in-part of my copending application Ser. No. 534,673, filed Mar. 16, 1966, now U.S. Pat. 3,457,194 issued July 22, 1969.

FIELD OF THE INVENTION This invention relates to monomers and to a process for preparing them. More particularly, the invention concerns 1-cyanobicyclo[1.1.0]butane monomers and a process for preparing them.

SUMMARY AND DETAILS OF THE INVENTION The novel monomers of this invention can be represented by the formula wherein R R R and R may be alike or different and are selected from hydrogen or hydrocarbyl of 1 through 18 carbon atoms which is free of aliphatic carbon-to-carbon unsaturation. By the term free of aliphatic carbonto-carbon unsaturation is meant that the hydrocarbyl group cannot contain any double or triple bonds other than those found in an aromatic ring system. Thus, the term hydrocarbyl set forth above includes such groups as alkyl, cycloalkyl, aryl, alkaryl, or aralkyl and the like.

The polymers prepared from the above-identified monomers are characterized by the recurring catenarian structural units of the formula wherein R R R and R are defined as above. The polymers are homopolymers prepared from the monomers of Formula I.

The term hydrocarbyl as used throughout the present specification and claims is synonymous with the term 3,530,163 Patented Sept. 22, 1970 hydrocarbon radical, i.e., an organic radical consisting only of carbon and hydrogen atoms. Examples of R R R and R in addition to hydrogen, include alkyl, cycloalkyl, aryl, alkaryl or aralkyl. The only prerequisites for the aforesaid hydrocarbyl groups are that the groups must be free of aliphatic carbon-to-carbon unsaturation and must contain 1-18 carbon atoms. Preferred herein are hydrocarbyl groups containing 1-12 carbon atoms, and particularly those containing 1-6 carbon atoms. Illustrative hydrocarbyl groups as defined hereinabove include alkyl groups, such as methyl, ethyl, t-butyl, hexyl, isooctyl, dodecyl, octadecyl and the like; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, methylcyclohexyl, 3,5-dicyclohexylcyclohexyl, cyclooctadecyl and the like; aryl groups such as phenyl, naphthyl, anthryl, p-phenylphenyl, p-biphenylphenyl, naphthacenyl, benzanthryl, chrysenyl and the like; alkaryl groups such as p-tolyl, p-cumenyl, 2,4,6-tributylphenyl, 9,10-diethyl-1-anthryl, 6-methyl-2-naphthyl, and the like; and aralkyl groups such as benzyl, phenylethyl, diphenylmethyl, a-naphthylethyl, 2-(2-anthryl)-ethyl, 4-(2-anthryl) butyl and the like.

The 1-cyanobicyc1o[1.1.0]butanes of Formula I are prepared by first reducing a S-cyanocyclobutanone of the formula H O: oN

HO OH v R3 R4 X ON wherein X can be chloro, iodo, bromo, benzenesulfonyl, parabromobenzenesulfonyl, paratolysulfonyl, or trimethylamino. For example, the hydroxy compound of Formula IV can be treated with thionyl chloride in the presence of pyridine to obtain the corresponding 1-cyano-3-chlorocyclobutane.

To obtain the monomers of this invention, the l-cyano- 3-substituted cyclobutanes of Formula V are treated with a strong base, such as sodium hydroxide, potassium hydroxide, tetramethyl ammonium hydroxide, potassium tertiary butoxide, and the like, to obtain the corresponding 1-cyano-bicyclo[1.l.0] butane of Formula I. This reaction is ordinarily carried out in the presence of an inert solvent, for example, hydrocarbons such as toluene, Decalin and light mineral oil, ethers such as tetrahydrofuran, diethyl ether, dioxane, dibutyl ether, diphenyl ether and the like. Pressure is not critical and superor subatmospheric pressure can be employed. Preferably, the reaction is carried out in the presence of an inert atmosphere such as nitrogen, helium, or the like. Temperature is not critical, but in general it is preferred to carry out the reaction in a temperature range of 20-+ 10 C. Reaction times are not critical; nor are reactant ratios. However, preferably a 1:1 molar ratio of base to the substituted cyclobutane is employed. The monomer is isolated by conventional procedures such as separation of organic and aqueous layers and distillation.

In general, the monomers of this invention are colorless liquids and are used to prepare polymers.

Homopolymers are prepared by the addition polymerization of a monomer of Formula I in bulk, in dispersion, in emulsion, or in solution in an inert organic solvent at a temperature of l to 160 C. in the presence of a free radical-generating initiator. Pressure above and below atmospheric pressure are operable. Atmospheric and super-atmospheric pressures are preferred.

Suitable solvents and/or dispersion media for the freeradical polymerization include water, hydrocarbons such as benzene and hexane, chlorinated aromatic hydrocarbons such as chlorobenzene, nitriles such as acetonitrile, amides such as dimethylformamide and N-methylpyrrolidone, sulfoxides such as tetramethylenesulfoxide, and the like. As indicated above, it is not essential that a solvent or dispersion medium be used, and bulk polymerizations can be carried out.

The free radical-generating initiators may be selected from a wide variety of compounds representative of this type of initiator. Included are the azo initiators, for example, a,a'-azodiisobutyronitrile, 1,l'-azodicyc1ohexanecarbonitrile, dimethyl a,a'-azodiisobutyrate and ot,aazodiisobutyramide, and the organic peroxides and hydroperoxides, for example, dibenzoyl peroxide, di-t-butyl peroxide, and t-butyl hydroperoxide. The initiators can be used in proportions ranging from 0.01 to 10 weight percent of the monomer being polymerized. Other sources of free radicals for initiating polymerization may also be used such as electron bombardment, ultraviolet light in the presence of a sensitizer, and the like.

Reaction times for preparing polymers from bicyclobutanes can vary from a few seconds (i.e. to several days, for example, two to three days or more depending on the particular monomer, initiator, solvent, and reaction temperature employed.

The result polymer, as will be evident from Formula II, will contain the indicated structural units arranged in more than one spacial configuration, i.e., the cyano group may be positioned cis or trans and thus the polymer may be isotactic, syndiotactic, and the like.

EMBODIMENTS OF THE INVENTION The following examples illustrate the invention in further detail but are not meant to limit the invention in any respect. Unless otherwise specified all temperatures are in C. and pressures are in millimeters of mercury.

EXAMPLE 1 Part A.--3-hydroxycyclobutanecarbonitrile To a stirred solution of 2.25 g. (0.060 mole) of sodium borohydride in 50 ml. of water was added with stirring a warm slurry of 19.0 g. (0.20 mole) of 3-cyanocyclobutanone in 50 ml. of water. The reaction Was mildly exothermic and ice cooling was used to maintain the temperature at 35. After the addition was complete, the solution was stirred at room temperature for 4 hrs. and was extracted continuously overnight with chloroform. The chloroform extract was dried and distilled to give 16.79 g, (86.5%) of 3-hydroxycyclobutanecarbonitrile in the form of a colorless liquid, B.P. 707l (0.33 mm.). Gas chromatography showed the compound to be a 70:30 cis-trans mixture.

Analysis.CalCd. for C H ON (percent): C, 61.84; H, 7.27; N, 14.42. Found (percent): C, 61.52; H, 7.26; N, 14.18.

This compound can also be prepared by catalytic hydrogenation in tetrahydrofuran solution using platinum on carbon as catalyst.

Part B.-3 chlorocyclobutanecarbonitrile To a stirred solution of 14.03 g. (0.145 mole) of 3- hydroxycyclobutanecarbonitrile, 12.0 g. (0.152 mole) of dry pyridine and ml. of chloroform was added at 05 a solution of 19.80 g. (0.166 mole) of thionyl chloride in 25 ml. of chloroform during 38 minutes. The solution was allowed to warm to room temperature with stirring. With continued stirring during 2 hrs., the temperature was raised to 56 and during an additional 2 hrs. to The solution was cooled and washed with 500 ml. of water containing 10 ml. of 37% hydrochloric acid, with 500 ml. of water containing 10 g. of sodium hydroxide, and with 500 ml. of water containing 10 g. of potassium chloride. It was dried with magnesium sulfate and distilled in a small spinning-band column to give 13.69 g. (81.7%) of 3-chlorocyclobutanecarbonitrile, B.P. 98 (28 mm.). Gas chromatography showed this compound to be a 83:17 cis-trans mixture.

AnalysisCalcd. for C H NCl (percent): C, 51.96; H, 5.23; Cl, 30.68. Found (percent): C, 52.04; H, 5.59; Cl, 30.70.

Part C.-1-cyanobicyclo 1 .1.0] butane To a stirred solution of 4.50 g. (0.0401 mole) of potassium t-butoxide in 30 ml. of purified tetrahydrofuran was added at 3 during 24 min. a solution of 3.90 g. (0.0338 mole) of 3-chlorocyclobutanecarbonitrile in 5 ml. of tetrahydrofuran. A nitrogen atmosphere was maintained during the addition. The thick, white slurry was stirred at 0 for an additional 83 min., at which time ml. of a saturated aqueous solution of potassium chloride was added. The tetrahydrofuran layer was separated and Washed twice with 25-ml. portions of potassium chloride solution. The aqueous layers were backwashed with 25 ml. of tetrahydrofuran. The organic layers were dried with magnesium sulfate and distilled in a small Vigreux column. A little 2,5-di-t-butylquinone was added to suppress possible radical polymerization. l-cyanobicyclo/ 1.1.0/butane, 1.73 g. (65%), was obtained as a color less liquid, B.P. 58 (26 mm.). The N.M.R. spectrum confirmed the assigned structure.

Part D.Poly-1-cyano-1,3-cyclobutane l-cyanobicyclobutane in a closed container at room temperature polymerized completely during 6 days to a tough, white solid. This dissolved completely in warm dimethyl formamide to give a clear solution from which the polymer was recovered in fibrous form by precipitation into methanol. The polymer, dried at possessed an inherent viscosity in dimethyl formamide of 3.00, indicative of very high molecular weight. On a heated bar, it did not darken or melt at 325.

EXAMPLE 2 Part A.1-cyano-bicyclo[1.1.0]butane A H. glass flask fitted with a stirrer, condenser and nitrogen bleed was dried with a heat gun and cooled under nitrogen. Under a nitrogen atmosphere there was placed in the flask 62.4 g. of 3-chlorocyclobutanecarbonitrile and 600 ml. of ether. The mixture was stirred and cooled to 12 C., at which temperature 66.0 g. of potassium t-butoxide was added portion-wise over a period of eight minutes. Stirring at 12 C. was continued for 15 minutes. About 20 g. of powdered solid carbon dioxide and about 10 grams of magnesium sulfate were then added, followed by 0.40 g. of 2,5-di-t-butylquinone and 0.40 g. of di-t-butylhydroquinone. The reaction mixture was filtered cold through diatomaceous earth under nitrogen, followed by a rinse of fresh ether. Ether was evaporated from the filtrate under water vacuum at 3545 C. The residue along with 0.2 g. each of 2,5-di-t-butylquinone and di-t-butylhydroquinone was transferred to a distillation flask and distilled at 8 mm. using a heating bath. Volatile materials were removed with the bath at C. With the bath at 55 C. there was distilled about g. of 1-cyanobicyclo[l.1.0]butane of high purity. It Was stored at 78 C. The N.M.R. spectrum either neat or in deuterochloroform was in agreement with the assigned structure. No olefinic unsaturation or tetrahydrofuran was detectable. The infrared spectrum of this sample supported the assigned structure and showed no hydroxyl or olefinic unsaturation.

Analysis.Calcd. for C H N (percent): C, 75.92; H, 6.37; N, 17.71. Found (percent): C, 76.14; H, 6.64; N, 17.41, 17.49.

Part B.Poly-1-cyano-1,3-cyclobutane To a stirred mixture of 15.8 g. of 1-cyanobicyclo[1.l.0] butane in 100 ml. of degassed distilled water, blanketed under nitrogen, were added a solution of 0.100 g. of potassium persulfate in 3 ml. of water and a solution of 0.0344 g. of sodium bisulfite in 1 ml. of water. Polymerization was noted by opalescence and curds began to form immediately. It was mildly exothermic, max. temp. 42. Reaction proceeded through a soft mush, a soft sheet on the walls, a solid sheet, and a thick white slurry.

Total time was 9 hrs. The slurry was filtered and washed with water. It was run through a blender with 400 ml. of water, filtered, and Washed. This was repeated with water and then with methanol. Drying under nitrogen in a vacuum oven at 80 gave 15.4 g. (98%) of white polymer, M.P. 350, no decomposition, inh (N-methylpyrrolidone) 2.63, at room temperature.

EXAMPLE 3 Poly-1-cyano-1,3-cyclobutane To a mixture of 10.4 g. of 1-cyanobicyclo[1.1.0]butane, 80 ml. of degassed distilled water, and 1.2 g. of the sodium salt of lauryl alcohol sulfate under nitrogen was added with stirring 0.100 g. of potassium persulfate in 3 ml. of Water and 0.0344 g. of sodium bisulfite in 1 ml. of water. Polymerization proceeded smoothly and mildly exothermically to form a creamy emulsion. Stirring was continued for 19 hrs. The emulsion was added to 300 ml. of saturated aqueous potassium chloride to form an extremely fine precipitate. This filtered slowly. The cake was broken up in a blender with 400 ml. of saturated potassium chloride solution and filtered, This was repeated. The product was blended three times with water, and dried in a vacuum oven at 80 under nitrogen to give 10.6 g. of polymer, ninh in dimethylformamide was 3.25 at room temperature.

EXAMPLE 4 Poly-l-cyano-1,3-cyclobutane Distilled 1-cyanobicyclo[1.1.01butane was dissolved in twice its volume of N-methylpyrrolidone and left at room temperature. It polymerized to an extremely viscous solution.

EXAMPLE 5 Poly-l-cyano-1,3-cyclobutane A solution of 3.1 g. of 1-cyanobicyclo[1.1.0]butane in 8.0 ml. of distilled dimethylsulfoxide was treated with 0.1 ml. of an 0.2 M solution of azobisisobutyronitrile in dimethylsulfoxide at for 16 hrs. A rigid glass formed.

EXAMPLE 6 Poly-l-cyano-1,3-cyclobutane The procedure of Example 5 was employed except that 1.2 g. of monomer in 20 ml. of tetramethylenesulfoxide were used. A film was cast from the resulting reaction mixture and dried in a vacuum oven at 80 C.

8 EXAMPLE 7 Poly-l-cyano-1,3-cyclobutane The procedure of Example 5 was employed except that 3.4 g. of monomer in 20 ml. of tetramethylenesulfoxide were used. This produced a clear viscous dope. Films were cast directly and dried at in a vacuum oven with nitrogen bleed. Tough, orientable, clear films were obtained. A sample of the polymer was isolated by precipitation of 7.0 g. of solution into methanol. After two blender washings, the dried polymer weighed 0.6 g. and had an inherent viscosity of 1.83 in N-methylpyrrolidone containing 5% LiCl at C.

EXAMPLE 8 Poly-l-cyano-1,3 -cyclobutane A solution of 12.8 g. of l-cyanobicyclobutane and 0.05 g. of azobisisobutyronitrile in 100 ml. of pure hexane was stirred at 75 under reflux and nitrogen. Granular particles formed rapidly and after 16 hrs., the reaction mixture was a thick granular mass. It was cooled and filtered. It was blended twice with water and once with methanol, 400 ml. each, and filtered very rapidly. The white polymer weighed 8.6 g. after drying.

EXAMPLE 9 Films from direct polymerization dopes A clear thick dope, prepared by direct polymerization of l-cyanobicyclobutane in tetramethylenesulfoxide, as in Example 6, was cast onto glass plates using a 0.01 or 0.02" doctor knife. The plates were placed in an 80 oven and subjected to full pump vacuum with a slight nitrogen bleed for 4 hrs. The films were sparkling clear, tough, and creasable.

EXAMPLE 10 :Films from isolated polymers A 5% solution of polymer, from Example 2, Part B, in N-methylpyrrolidone was prepared using an air-driven double-disc stirrer and warming to 65. A trace of gel was removed. The dope was cast 'as in Example 9 to obtain clear tough films.

EXAMPLE 11 Direct preparation of shaped objects A N.M.R. tube was filled with freshly distilled l-cyanobicyclobutane. After 6 days at room temperature it had completely solidified to a translucent rod. The glass tube was broken open and removed leaving a tough flexible rod of polymer.

EXAMPLE 12 Part A.--2,2-dimethyl-3-cyanocyclobutanone egg 0H3 CH3 CH3 To a slurry of 119.1 g. (0.983 mole) of 2,2-dimethyl- 3-methylenecyclobutanecarbonitrile and 0.25 g. of osmium tetroxide in 1.23 liters of water there was added with stirring during 4 hours, 479 g. (2.24 moles) of sodium metaperiodate. The reaction temperature was gradually raised from 6595. At the end of this time, the organic phase had disappeared, and a granular slurry of salts was present. The reaction mixture was left to cool and stir overnight. The solids were filtered and Washed well with chloroform. This filtrate was used to continuously extract the aqueous filtrate. The chloroform extract was dried and evaporated. Distillation from mercury gave a crude semisolid distillate, B.P. 5682 (0.4 mm.). This was redistilled in a spinning-band column to give 13 fractions, B.P. 23-45 (0.4 mm.). At -35, fractions 7-13 crystallized. They were recrystallized twice from 1:1 ether-pentane at -35 to give 20.0 g. (16.5%) of a white solid melting at about 28.

7 Analysis.-Calcd. for C'IHgON (percent): C, 68.27; H, 7.37. Found (percent): C, 68.12; H, 7.21.

Part B.2,2-dimethyl-3-cyanocyclobutanol CH3 CH3 CH3 CH3 To a stirred solution of 1.70 g. (0.18 equivalents) of sodium borohydride in 50 ml. of water there was added 18.9 g. (0.153 mole) of 2,2-diInethyl-3-cyanocyc1obuta none. The reaction was exothermic and was maintained at 3545 with water cooling. The addition required 17 min., and the reaction mixture was stirred for an additional 3 hours. The oily upper layer was taken up by extraction 5 times with 60-m1. portions of chloroform. The organic layers were dried and distilled to give 17.9 g. (95.5%) of a waxy colorless solid, B.P. 70 (0.25 mm.).

Analysis.Calcd. for C H ON (percent): C, 67.17; H, 8.86; N, 11.19. Found (percent): C, 66.44, 66.82; H, 8.25, 8.53; N, 11.13.

The infrared spectrum supported the assigned structure and showed that no carbonyl group was present.

Part C.3-benzenesulfonyloxy-Z,2-dimethylcyclobutanecarbonitrile CH3 CH3 CH3 CH3 To a solution of 16.0 g. (0.128 mole) of 3-hydroxy- 2,2-dimethylcyclobutanecarbonitrile in 90 ml. of pyridine at there was added 26.0 g. (0.147 mole) of benzenesulfonyl chloride during 17 minutes with stirring. The reaction mixture was stirred at 0 for an additional hour and left at 0 overnight. It was poured into 600 g. of ice and Water and stirred for 40 minutes. The mixture was neutralized with 250 ml. of cold 6 N hydrochloric acid and extracted 3 times with 200-ml. portions of ether. The combined organic layers were washed with 50 ml. of saturated potassium chloride solution, dried and evaporated. The residue was stirred at 60 and 2 mm. for 3 hours to leave 30.4 g. (89.5%) of 3-benzenesulfony1oxy- 2,2-dimethylcyclobutanecarbonitrile.

Analysis.Calcd. for C H NO S (percent): C, 58.85; H, 5.70. Found (percent): C, 59.24; H, 5.98.

Crystallization from hexane-ethyl acetate (2:1) at 0 gave the crystalline benzenesulfonate, M.P. 72-74", in good yield.

Analysis.-Found (percent): C, 58.80, 58.89; H, 5.80, 5.73.

Part D.2,2-dimethyl-l-cyanobicyclobutane CeHsSOzO CN KOC4Hn(t) To a solution of 5.0 g. (0.0189 mole) of crystalline B-benZenesulfonyloxy 2,2 dimethylcyclobutanecarbonitrile in 100 ml. of ether there was added with stirring 2.12 g. (0.0189 mole) of potassium t-butoxide. After the mixture had been stirred for 5.3 hours at room temperature, it was a thin slurry. To the mixture were added 0.3 g. of 2,5-di-t-butylquinone, about 5 g. of Dry Ice and, dropwise, 3 ml. of water, to form a granular precipitate. Magnesium sulfate was added, and the mixture was filtered under nitrogen pressure through Celite, which was rinsed with fresh ether. The filtrate was concentrated and distilled to give 1.52 g. (75.0%) of 2,2-dimethyl-l-cyanobicyclobutane, B.P. 50-51 (9 mm.).

Analysis.Calcd. for C H N (percent): C, 78.46; H, 8.47. Found (percent): C, 78.18; H, 8.84.

0 Part E.Polymerization of 2,2-dimethyl-1- cyanobicyclobutane solution. The diiferential thermogram showed an endorm beginning at 307 with its peak at 330.

EXAMPLE 13 Part A.2,2,4,4-tetramethyl-3-cyanocyclobutanone CN ON I NMP CH3 CH3 NaH CHaI H CH3 H CH3 Twenty grams of a 54% dispersion of sodium hydride in mineral oil (i.e. 0.448 mole of NaH) Was cleaned under nitrogen with two 200-ml. portions of pentane. It was covered with 100 ml. of N-methylpyrrolidone. To this suspension there was added with stirring a solution of 9.51 g. (0.10 mole) of 3-cyanocyclobutanone in 70 g. (0.493 mole) of methyl iodide. The addition was carried out during 2.2 hours with mild cooling to maintain the temperature at 2530. At the end of the addition, 8.43 liters of gas had evolved. The mixture was stirred overnight leaving a pan of water around the flask. After this 14-hour period, the total volume of gas was 12.64 liters and the reaction mixture was semisolid. It was poured into 400 ml. of water and ice and extracted 5 times with 200 m1. portions of pentane. The combined organic layers Were backwashed with 50 ml. of saturated potassium chloride solution, dried and distilled. The distillate boiled at 40 (0.25 mm.) and weighed 6.99 g. It was semicrystalline. Two recrystallizations from 10 m1. portions of pentane at and two recrystallizations from 15 ml. portions of pentane at -35 gave 3.00 g. (19.8%) of 2,2,4,4-tetramethyl-3-cyanocyc1obutanone, M.P. 57-59".

Analysis.Calcd. for C H ON (percent): C, 71.49; H, 8.67. Found (percent): C, 71.40, 71.75; H, 8.67, 8.74.

Part B.2,2,4,4-tetramethyl-3-cyanocyclobutano1 HsC To a stirred, nitrogen-swept solution of 2.0 g. (0.0528 mole) of sodium borohydride in 50 ml. of water there was added 6.00 g. (0.0397 mole) of 2,2,4,4-tetramethyl- 3-cyanocyclobutanone. The solution was stirred at 25 for 4.5 hrs. and then extracted with four ml. portions of ether. The ether layer was washed with 25 ml. of saturated KCI solution, dried over magnesium sulfate and concentrated on a rotary evaporator. The 4.6 g. of crystals obtained from the ether layer was sublimed at 80120 (0.3 mm.) to yield 4.3 g. (70.5%) of 2,2,4,4- tetramethyl-3-cyanocyc1obutanol, M.P. 1l1.31l6.3. The infrared spectrum showed no carbonyl groups in the product and generally supported'the assigned structure.

Analysis.-Calcd. for C H ON (percent): C, 70.55; H,9.87; N, 9.14. Found (percent): C, 70.91, 70.56; H, 9.79, 9.85; N, 8.98, 9.10.

Part C.--3-benzenesulfonyloxy-2,2,4,4-tetramethy1- cyclobutanecarbonitrile 10 Analysis-Calcd. for C H N (percent): C, 79.95; H, 9.69. Found (percent). C, 78.85, 78.82; H, 9.71, 9.59.

Part E.Polymerization of 2,2,4,4-tetramethyl-1- CN N b, 1 b H30 CH8 H30 1 CH3 cyano icyc o utane CH5N CoI-I5 02O1 5 The monomer when treated with a standard aqueous HaC CH: HsC 4) CH3 emulsion polymerization recipe (7 ml. 0 free H O, 1.25 OH CGHESOZ ml. of K S O [1.0 g. in 125 ml. H O], 0.5 ml. of

H+/Fe++ 16 ml. 0.1 N H SO 0.004 To an ice-chilled solutlon of 4.55 g. (0.030 mole) of 2 g 2,2,4,4-tetramethyl-3-cyanocyclobutanol in 30 ml. of 4( 2)2 4' 2 pyrldme added a .(9- 9 of Pyndme 80 ml. 0 free E 0], 1.21 ml. of N21 S O [2 g. in 100 q a 16 s wlth Vlgorous stlrrmg- The ml. H 0], and 0.7 ml. soap solution [1.0 g. sodium lauryl tion was kept in ice for 5.5 hrs. and then left at 5 for sulfate in 10 02 free H201) at f 2 While 40 The sohfuon was mto a s s F under N gave no polymer. When AIBN (azobisisobuexcess ice water with magnetic stirring. Crystallization 1.) tyronitrile) was added to the recipe, a 30% yield of white occurred so the mixture was filtered, triturated and Polymer was obtained rinsed l wlth waten h sohd was E F over When the l-cyano-3-alkylenecyclobutanes shown in 2 5 to glve 8- of sohd, 94 96 The Infrared column 1 of Table I are subjected to ozonolysis in the spectrum showed 6 5 2 to be Present and no procedure of Cripps et al., J. Am. Chem. Soc. 81, 2723-8 The sohd was recrystalhzed from Of hsxane P 1us (1959), the substituted 3-cyanocyclobutanones of column 3 Of ethyl acetate and filtered whlle f- Wlth coohng 2 are obtained. When these in turn are substituted for soft crystals came out of the solutlon which was filtered 3 cyanocyclobutanone in the procedure of Example 1 and P p y- The Yleld Was of crystals above, the 1-cyanobicyclo[1.1.0]butanes of column 3 are 0 e 'whlch m ted fro 977-987 NMR and IR Spectra obtained. These yield the corresponding polymers when supported the proposed structure. treated according to the procedure of Example 2, Part B.

TABLE I Item (1) 1-cyano-3-alkylenecyclobutane (2) 3-cyanoeyclobutanone (3) l-eyanobicycloIl.1.0]butane.

1 l-eyano-Z,2-diethy1-3-methyleneeyclobutane. 3oyan02,2-diethylcyclobutanone 1-cyano-2,Idiethylbicyclofl.1.0]butane. 2. l-cyano-2,2-di(n-butyl)-4-methy1-3-methyl- 3-cyano2,2-di(n-butyl)-4-methyleyelobuta- 1-cyano-2,2-di(n-butyl)-4-methylbicyclo[l.1.0]

eneoyclobutane. none. butane. 3 1cyalgroi2-dodeeyl-3-methylene 4-phenylcy- 3-cyano-2-dodecy1-4-phenylcyelobutanone 1-eyano-dodeeyl-4-phenylbicyelo[1.1.0]butane.

e o u ane. 4 2-n-buty1-1-cyano-3-(Q-heptadeeylidene)-2- 2-n-butyl-3-cyano-2-methylcyclobutanone Z-n-butyl-l-eyano-2-methylbieyclo[1.1.0]bumethylcyclobutane. tane. 5 1-cyano4-deeyl-3-is0pr0py1idene-2,Z-di- 3-eyano-4-decy1-2,Z-dimethylcyelobutanone.. l-cyanc-tdecyl-Z,2-dimethylbicyclo[1.1.0]bumethylcyclobutane. tane. 6 l-eyano-4-cyelohexyl-2-eyelopropy1-2- 3-cyano-4-cyclohexyl-2-cye1oprcpy1-2- 1-eyano-4-cyclohexyl-Z-cyclopropyl-2-n1ethylmethyl-B-methylene-cyclobutane. methyleyclobutanone. bicyelo-[1.1.0]butane. 7 2-benzyl-1-cyano-2-methyl-3-methylene-4- 2-benzyl-3-cyano-2-methy1-4-tridecylcye1o- 2-benzy1-1-cyano-2-methyl-4-tridecylbieyclotridecylcyclobutane. butanone. [1.1.0]butane. 8 l-ezyano-3-rnethylene2,Z-diphenylcyclobu- 3-cyano-2,Z-diphenylcyclobutanone 1-cyano-2,2-diphenylbioyolo[1.l.0]butane.

3.116. 9 1-cbyano3-methylene-2-(fl-naphthyl)cyclo- 3-cyano-2-(fi-naphthyD-eyclobutanone 1-cyano'2-(fi-naphthyDbioyclo[1.1.0.]butane.

utane. 10 1-eyan0-2-(a-naphthyl)-2-pheny1-3-(1- 3-cyano-2-(a-naphthyl)-2-phenyleyc1obu- I-cyanQ-Z-(a-naphthyl)-2-phenylbicyc10[1.1.0]

phenyl-l-p-tolyl)-methy1eneeyclobutane. tanone. butane. 11 1-eyagof-cyclohexylmethy1-3-metl1ylenecy- 3-cyano-2cyclohexylmethylcyclobutanone 1-cyano-2-eyclohexylmethylbicyclo[1.1.0]buc o u ane.

tane.

Analysis-Called. for C H O NS (percent): C, 61.47 H, 6.53. Found (percent): C, 61.58; H, 6.52.

Part D.-2,2,4,4-tetramethyl-1-cyanobicyclobutane Run 1 E1220 KO C4H9-t OSOzCaHa At 10, potassium t-butoxide (2.58 g., 0.023 mole) was added in portions, with no visible reaction, over a 10-min. period to a solution of 2,2,4,4-tetramethyl-3- benzenesulfonyloxycyclobutanecarbonitrile (5.87 g., 0.02 mole) in 60 ml. of ether. The mixture was allowed to come to room temperature with stirring, stirred for 2 hours and cooled in an ice bath. Phenothiazine, Dry Ice and water (8 ml.) were added to the mixture. The ether layer was separated. The salts were extracted with ether ,(25 ml.). The ether layers were washed twice with 10 ml. portions of saturated KCl soln. After drying over MgSO the mixture was concentrated on a rotary evaporator and distilled from phenothiazine into a Dry Ice chilled receiver to yield 1.28 g. (47.4%) of product, B.P. 25-26 (0.2 mm). The NMR and infrared spectra supported the proposed structure.

For convenience and because of availability, R R R and R will preferably be hydrogen, lower alkyl or phenyl. Most preferably, R through R Will be hydrogen.

The polymers described above are of extremely high molecular weight having inherent viscosities of 1.2 or more. The infrared spectrum of the polymer form Example 1-D recorded CN groups at 4.47 (m),u, and CH groups at 3.35 (m) and 3.39 (m),u. The homopolymers are high melting, tough, non-brittle and form self-supporting films or fibers. The polymers can be drawn to form oriented fibers of high tensile strength. For example, a polymer prepared as in Example 5 was drawn from dimethylsulfoxide at about C. to form a fiber. The polymers can be easily cast into films, shaped objects, or drawn into fibers from conventional solvents such as dimethylformamide, N-methylpyrrolidone, tetramethylene sulfoxide, and the like. Thus, the polymers are useful in a wide variety of applications as coating compositions, self-supporting films, and fibers, especially those applications wherein strong, non-brittle films or fibers are desired. For example, the direct preparation of spin dopes is accomplished by polymerization of the monomer in tetramethylenesulfoxide or N-methylpyrrolidone solution.

The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations are to be understood therefrom. The invention is not limited to the exact details shown and described, for obvious modifications will occur to those skilled in the art.

The embodiments of the invention in which an exclu sive property or privilege is claimed are defined as follows:

11 12 1. A compound of the formula References Cited i UNITED STATES PATENTS H ON 3,234,264 2/1966 Blanchard 260464 3,340,290 9/1967 Blanchard 260464 5 3,393,159 7/1968 Blanchard 26063 X 3,457,194 7/1969 Hall 260464 XR wherein R R R and R may be alike or different and are selected from hydrogen or hydrocarbyl of 1 JOSEPH P, BRUST, Primary Examiner through 18 carbon atoms Which is free, of aliphatic carbon-to-carbon unsaturation. 0 US. Cl. X.R.

2. The compound of claim 1 wherein R R R and p R may be alike or difierent and are selected from 3 122 3 6 -4, 32.6, 33.6, hydrogen, lower alkyl, or phenyl.

3. The compound of claim 1 wherein R R R and R are each hydrogen. 15 

